sphenobasilar synchondrosis

sphenobasilar synchondrosis (sfēˈ·nō·baˑ·zi·ler singˈ·kôn·drōˑ·sis),

n the cartilaginous junction of the posterior surface of the body of the sphenoid bone and the anterior end of the basal portion of the occipital bone.
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Sphenobasilar synchrondosis.